Hetton Colliery or Hetton Lyons Colliery. The 1st edition OS mapping also shows a Gas Works within the site. There were two pits - Blossom Pit and Minor Pit. This was the southern terminus of the Hetton Railway (HER 2848). The colliery (and railway), laid out by George Stephenson and built by his brother Robert, was started in 1822. This was historically one of the most important mines in the Durham Coalfield. Hetton Pit was the very first mine from which coal beneath the magnesian limestone plateau of north east Durham was extracted. Geologists had previously said that good quality coal did not exist below the limestone. The pits were ventilated by furnaces and boiler fires. Shaft sidings and stables were lit by electricity. Its success led to the opening out of the whole of the north east Durham coalfield and shaped the history and growth of the area for the next 150 years. The coming of the mine had a huge impact on the economy and population of Hetton. Alongside the pit were cokeworks, brickworks, colliery blacksmith's, joiners' shops, engine repair shops and wagon sheds. There were four places of worship belonging to the Baptists, Wesleyan Methodists, Primitive Methodists and Kilhamite Methodists. And a Chapel of Ease. An explosion on 20 December 1860 killed 22 people. TH Hair drew a picture of the colliery. The Hetton Coal Company became the Lambton and Hetton Colleries Ltd in 1911, the Lambton Hetton & Joicey Colleries Ltd in 1923 and in 1947 it was taken over by the National Coal Board. The colliery closed in July 1950. A number of colliery buildings survive - the main complex of decorative stone-built colliery buildings is on the north side of colliery lane. On the south side is a stone fronted building with decorative arched windows now known as Trainor's Depot with other colliery buildings to the rear. Next to this is the brick-built Lyons Garage of later date. The former colliery worker's cottages on Lyons Avenue, where Robert Stephenson once lived, have a commemorative plaque on the gable end. The former Youth Centre to the rear of the cottages is probably also a former colliery building. Within Hetton Lyons Industrial Estate, the brick building now occupied by Hall and Blenkinsop, is a former engine house for the colliery. Trainor's Depot and Lyons Garage were recorded by ASUD in July 2004 prior to demolition. Trainor's depot dates to the second half of the C19, Lyons Garage is a brick engine shed dating to the 1920s or 30s.